The present invention relates generally to an oxygen trainer for use by athletes to increase their inspiratory muscular endurance.
The restriction of airflow into the mouth and lungs during athletic or aerobic conditioning enables the body to adjust to a higher level of functioning with less oxygen. This may in turn strengthen the lungs by improving their aspiratory muscular endurance. Short of engaging in strenuous exercise or training at high altitude, it is difficult to simulate the incremental restriction of airflow into the lungs in order to achieve improved aspiratory muscular endurance.
It is understood that there are prior art devices that can simulate the restriction of airflow into the lungs in order to activate respiratory muscle endurance training. For instance, U.S. Patent Application No. 2008/0096728 discloses a respiratory muscle endurance training device wherein a duck-bill valve is used as a slit valve. U.S. Pat. Nos. 5,658,221, 5,899,832, 6,083,141, and 6,500,095 all disclose portable personal breathing apparatus that have a pair of coaxial cylinders each having slots which can be selectively aligned or misaligned to provide differing breathing resistance. U.S. Pat. No. 6,450,969 discloses a device for measuring inspiratory strength which uses a series of slots and holes to provide differing breathing resistance. U.S. Pat. No. 4,739,987 discloses a respiratory exerciser having a plurality of holes which are radially offset from the center of a circular base to affect regulation of breathing resistance. U.S. Pat. No. 4,601,465 discloses a device for stimulating the human respiratory system wherein a perforated disc having plural apertures may be removably mounted to the portable device to regulate breathing resistance. However, it is understood that none of these devices disclose removable resilient inserts whose openings have varying dimensions that provide a variable resistance for increased inspiratory muscular endurance both during the intake and exhaust of oxygen.
Accordingly, there is a need in the art for an oxygen trainer assembly having application to various athletic or aerobic training activities that can be readily modified to provide a variable resistance for oxygen intake and exhaust in order to increase inspiratory muscular endurance while at the same time being portable, convenient to clean, relatively inexpensive, and reliable.